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Running Your Electric Meter Backwards

kdawson posted more than 7 years ago | from the power-to-the-peeps dept.

Power 526

kog777 writes to note a story in International Business Times about "net metering," or generating your own power without disconnecting from the grid. Forty states have laws allowing individuals to do this, and many of them offer subsidies and tax breaks for people who do. From the article: "When the sun shines bright on their home in New York's Hudson Valley, John and Anna Bagnall live out a homeowner's fantasy. Their electricity meter runs backward. Solar panels on their barn roof can often provide enough for all their electricity needs. Sometimes — and this is the best part — their solar setup actually pushes power back into the system."

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526 comments

You can do the same thing... (5, Funny)

Centurix (249778) | more than 7 years ago | (#17720664)

With a Ferarri when you stick it in reverse.

Re:You can do the same thing... (0, Funny)

Anonymous Coward | more than 7 years ago | (#17720672)

I saw that movie!

Re:You can do the same thing... (2, Funny)

ForestGrump (644805) | more than 7 years ago | (#17720696)

Staying home pretending to be sick instead of going to school. I see it has really paid off and now you read /. instead of doing something productive with life. Tho, not like I'm doing any better.

Grump

OT, sick day scams... (2, Insightful)

zippthorne (748122) | more than 7 years ago | (#17720856)

The odometer only had 3 digits. Why didn't they just run it forward till it turned over?

Surely I wasn't the only one who was bothered by this.

Re:OT, sick day scams... (1, Funny)

Anonymous Coward | more than 7 years ago | (#17721178)

Repeat after me:

It's not real. I am a geek.

;)

Re:OT, sick day scams... (0)

Anonymous Coward | more than 7 years ago | (#17721620)

Have you ever even SEEN a car?? There's a trip odometer and the main odometer. The main odometer has at least 5 digits, and usually 6 or 7.

Re:You can do the same thing... (1)

ogopogo (1054718) | more than 7 years ago | (#17720884)

John Williams (Consumertronics) has run ads for years selling methods and techniques for stopping power meters and even getting them to run backwards. No need for solar or wind generators. See: http://www.google.ca/search?hl=en&q=consumertronic s+%22stopping+power+meters [google.ca]

Re:You can do the same thing... (4, Funny)

Anonymous Coward | more than 7 years ago | (#17720984)

One method that John doesn't cover is tapping into your neighbors connection to the grid. There is this really old couple that lives next to me. They appear to be completely oblivious to the fact that they get $500+ utility bills every month, yet they live in an 750 square foot house with no central heat and air. I've found that my energy bills have been cut dramatically, even though I have remodeled my garage so that there is a server room with AC running 24/7 for my 20 servers.

Thanks god for social security.

Google ADMITS: I am not a Google SHILL !! (-1)

Anonymous Coward | more than 7 years ago | (#17721054)


Google ADMITS: I am not a Google SHILL !!

El! (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#17720666)

El posto uno!

What is the story? (4, Informative)

Anonymous Coward | more than 7 years ago | (#17720674)

Err, this has been mentioned countless times. I really fail to see how this story adds anything. Yes, you can put power back into the grid and get paid. This is not new, and this is hardly a little known fact.

realities? (4, Interesting)

bcrowell (177657) | more than 7 years ago | (#17720698)

I live in Southern California, and one side of my roof faces south, so I should be a prime candidate for this. However, I have some concerns about actually doing it. For one thing, when we bought the house, 10 years ago, the sellers were just in the process of replacing the roof, and while they were at it, they removed the solar water heater for the pool. If you figure we have 15 years left on this roof, I have to wonder whether an expensive photovoltaic system will end up going the same way as the solar water heater. Another question in my mind is the uncertainties related to the craziness California has been seeing in electric rates, as well as uncertainties about when is the right time to buy photovoltaics, given that the technology is advancing rapidly. And then there are all the other things that might be easier and more practical than installing solar panels. I replaced a bunch of incandescent bulbs with compact fluorescents last month. I've never been able to get power management to work properly on my Ubuntu box. One of the big electricity hogs in our house is the pool pump, and there's not much you can do about that; if you don't pump long enough on the pool every day, it turns green.

Re:realities? (4, Insightful)

scoot80 (1017822) | more than 7 years ago | (#17720748)

One big issue is: how long will they take to pay themselves off? They aren't cheap. All you have done is pre-paid your electricity for the next 5-10 years (however long they end up paying themselves off over), and that is only on the sunny days. Unless you have energy storage (maybe you can fill the roof with lead acid batteries...), on every bad day you'll be draining juice back from the electricty company, so the time its taking to pay itself off is just getting longer...

In the end, I think the choice is whether you want to help make the world greener, or you just plain don't give a rats.. most people don't give a rats ass, and so solar panel prices will stay up. Maybe the goverment should make it mandatory that new buildings have solar panels installed (does that already exist)? Here in Aus, new buildings have to have solar powered heating and sunlights.. but then again, we live in an oven of a country..

Re:realities? (4, Funny)

Mongoose (8480) | more than 7 years ago | (#17720900)

...and that is only on the sunny days.


Have you ever lived in Southern Califorina? If there is ever a could in the sky people run off the street to take shelter in the nearest building. Don't ask what happens in a freak rain shower! Drizzle of doom...

Re:realities? (5, Interesting)

Stephen Samuel (106962) | more than 7 years ago | (#17721002)

There's no need to store energy if you have an agreement with the power company -- When you have extra power, they pay you for it. When you need extra power you pay them for it. You are effectively 'storing' your extra power in the power grid with near 100% effectiveness (better than batteries -- unless the power grid collapses).

Although solar cells aren't cheap, the prices have come down, and efficiency has gone up over time. It's kinda like buying a computer... If you're waiting for the fastest computer to come out before you buy yours, chances are you're reading this on a TI57 programmable calculator.

If you buy now, your savings start now. If you cover the cost of the cells in saved energy bills and rebates from the power company, then the fact that a 'better' system comes out later doesn't hurt you that much.... Once you have covered the original cost, you can always replace the system with a new one, and you really don't lose anything. (but you get the satisfaction of preventing the waste of a few barrels of increasingly precious oil, and slowing global warming by just a smidgen).

Before you do something, ask yourself "what would happen if a million people did this"?

Re:realities? (1)

arivanov (12034) | more than 7 years ago | (#17721086)

7-11 years depending on the region, installation, etc for a suitable system. Usually longer than most people own a house. This is the primary reason why they are so rare.

like computer evolution (4, Interesting)

choseph (1024971) | more than 7 years ago | (#17721146)

Every time an article like this comes up, people are nice enough to point out problems with solar (gunk to create, $$ to invest, wears out). Still, I have to say the idea continues to be exciting

The appeal comes with the similarities to computer evolution and balance (mainframe/personal) and the internet (grid computing). People can keep telling me it isn't worth it or will never happen (or will be super-inneficient), but I'm always going to hold out for that internet-like energy grid. All your Googles and p2ps working together...figure out a way to sell ads over power and maybe you'll get free power from Google itself. Hmmm...maybe I should patent ads over power lines before it is too late.

Prepay your electric bill, or buy the electric co. (4, Insightful)

patio11 (857072) | more than 7 years ago | (#17721198)

>>
All you have done is pre-paid your electricity for the next 5-10 years
>>

60 months worth of your electric bill, call it an average of $100 a month, is $6,000. If you "pre-pay" that by rolling it into your home loan ("Build me a house and make sure it has a pool and solar power!"), it will end up costing you more (rough guesstimate is $7,300). If instead of buying photovoltaic cells you buy shares in your local electric company, you'll get about $120 to $240 a year in dividends (power companies often have a 2-4% yield), and your while your photovoltaic cells depreciate every year and require maintenance, your shares will probably appreciate and you'll never have to patch them up. (You'll have to pay the electric company for those 10 months of the year that dividends don't... then again, you get the security of knowing you'll never have to pay them extra just because its cloudy.) When you move in 15 years, rather than uninstalling or replacing them at your expense, you can just sell them and take your profits.

>>
In the end, I think the choice is whether you want to help make the world greener, or you just plain don't give a rats
>>

I don't give a rat's hindquarters for Green theology but don't mind conservation. Thats why I buy shares in companies which own nuclear power plants. Its cleaner than solar and has economies of scale. Yes, I said cleaner than scale: the energy cost from constructing solar panels keeps them net-energy-negative for about a decade (!) and when they die out after just over a decade (!) you have to dispose of them, and per megawatt hour generated you'll have to dispose of a heck of a lot more solar panels than radioactive waste. I don't invest in solar companies because at the moment they still haven't licked the whole "Making our products net energy producers" problem and until they do my only hope to profit from that investment would be hoping solar's massive government subsidies continue and expand. While I think that is certainly possible, I feel that if the current or a future administration wants to dump a couple billion into the solar industry, my nukes will get a similar largesse.

Sidenote: If you have an aversion to nuclear power, I understand and accept that. I don't eat meat on Fridays in Lent and we can both agree that our separate faiths are mutually harmless. One piece of advice though. Spend your money on a decent job of insulating your house -- you'll require less kwh from the grid, and on a per-dollar basis you'll save more kwh spending on insulation (and installation) than you will on buying solar power.

Re:realities? (1)

marcovje (205102) | more than 7 years ago | (#17721208)


Yes. Note that the articles
- mentions putting it on the barn, not an house. Barn is probably way larger in roof surface.
- no analysis of cost/benefit as you say.
- falls into the pseudo environmental category. If the production of something with a green principle is quite environmentally damaging, and the "green" benefit is low, the net result can still be _more_ polution. That's about the first thing they learn you in any engineering course about the environment, yet journalists seem to miss that en-masse.

Re:realities? (2, Insightful)

iminplaya (723125) | more than 7 years ago | (#17720760)

...as well as uncertainties about when is the right time to buy photovoltaics...

Now, or you'll die waiting for the "perfect" system. You don't have to do it all at once. Start with some small panels to just run the pump for now.

Re:realities? (2, Interesting)

Keebler1175 (748412) | more than 7 years ago | (#17720766)

There is a new company that making it easy to choose solar, even in the case of an upcoming roof replacement. They rent you the equipment, and will remove it one time free of charge, and set it back up if you need to replace your roof. There are no maintenance costs, you pay for only the energy the system produces, you lock in last years electricity rates through your entire contract, and you only have to put up a security deposit at the time of installation. I signed my own home up, and can't wait for the install.

Re:realities? (5, Informative)

Eivind (15695) | more than 7 years ago | (#17720786)

The reality is that on average, photovoltaics costs more to install and maintain than the power they produce is worth, thus on the average you're poorer *with* photovoltaics than without.

This is however only true on average. If, for example, you live in an area where you get tax-breaks or subsidies for installing, then this can be enough to break even. In Germany, for example they have a "100.000 roofs" program where you're guaranteed a price about 3 times market-price for the power you produce for the next 15 years. That is *more* than enough to make it profitable.

Solar water-heaters on the other hand are beneficial. Especially if you live in an area with plenty of sun *and* have a large family that likes to frequently shower in the summer, it can be a huge win. There are substantial savings from installing them at the same time one installs roofing, so your best bet is probably going to be to install them at the same time your roofing needs replacement anyway, rather than separately.

The *most* beneficial investment however is building/buying a well-insulated house with balanced ventilation. This saves power in summer for AC, and in winther for heating. And a well-insulated house doesn't have higher maintenance-costs than a poorly insulated one.

Re:realities? (4, Interesting)

TapeCutter (624760) | more than 7 years ago | (#17720898)

"The *most* beneficial investment however is building/buying a well-insulated house with balanced ventilation. This saves power in summer for AC, and in winther for heating. And a well-insulated house doesn't have higher maintenance-costs than a poorly insulated one."

From my own experience, I paid to get insulation pumped into the roof a couple of years after I moved into my first house in the early 90's, no tax breaks or subsidies at that time so I paid the full price. It cut my heating bill in half (well, almost) and it paid for itself in less than 2yrs. Not sure about this, but I think it is compulsory for new buildings to be insulated here in Australia, they all seem have it built in.

Re:realities? (-1, Flamebait)

Bios_Hakr (68586) | more than 7 years ago | (#17721032)

First off, let me admit that I'm a self-described anti-hippy. Here's a classic example of why.

Why should all the consumers in an area pay higher prices just so a "hippy" can feel good about using solar cells?

If the technology is viable and profitable, let it grow. If, however, it's only profitable after subsidies, then it's a waste of time, money, and resources.

Re:realities? (1)

Propaganda13 (312548) | more than 7 years ago | (#17721056)

If I remember right the solar averaged $.25/kwh and I pay $.09/kwh for grid power. It makes more sense for me to store it for my own use. I'm in the Midwest.

Re:realities? (1)

Propaganda13 (312548) | more than 7 years ago | (#17721126)

I shouldn't post to Slashdot when I'm in a daze.

I pay around $.099/kWh and around $.128/kWh with the facility charges, etc. figured in. If you're still on the grid while using solar, you'll still pay those facility charges, but will save a little on sales tax. Consider the facility charges as payment for using the grid as a battery as long as they pay retail for your extra juice. Ignore my babbling in the original post.

http://solarbuzz.com/SolarPrices.htm [solarbuzz.com] shows residential solar power at $.37/kWh in a sunny climate and $.82/kWh in a cloudy climate.

Re:realities? (2)

arachnoprobe (945081) | more than 7 years ago | (#17721216)

The *most* beneficial investment however is building/buying a well-insulated house with balanced ventilation. This saves power in summer for AC, and in winther for heating. And a well-insulated house doesn't have higher maintenance-costs than a poorly insulated one.
Insulation is so good that these days, heating is the least of your problems. A friendly family of mine is living in a 2-story-energy-efficient (certified) house, they never need any heating (middle europe), normally they have cooling problems. even in winter. They have special "slots" to let in cold air, which are needed even in the winter.

Re:realities? (1)

dada21 (163177) | more than 7 years ago | (#17721342)

Bullshit. There are no free grants or tax breaks -- those are paid by everyone else.

Don't start spewing that garbage. If you make 3x market value, the taxpayer is paying the other 2x over market, plus the bureaucratic overhead, too.

Re:realities? (2, Interesting)

sireasoning (576345) | more than 7 years ago | (#17720872)

You might want to check out the REnU program at Citizenre, http://renu.citizenre.com/ [citizenre.com]

The gist of the program is that they will buy, install and maintain a solar electric system for your home. You then sign a contract and agree to pay them for the electricity generated by the solar system. You can sign a contract for 1, 5, 10 or 25 years and you get a fixed rate per Kilowatt throughout the contract period that is your current rate off the grid at the time of sign-up. So if you are currently paying 10 cents a Kilowatt when you sign up for a 25 year contract, then that price is fixed for 25 years.

The beauty of this program is that it allows any homeowner to have a solar system without the huge upfront costs. You will need to continue service with your current electric company as this is a grid-tied system (no batteries). You will need to be in a state that has a net-metering law for it to be of any use (as they will include enough panels to feed the grid during sunny days and then you can draw back your energy credits at night off the grid.) Even though it is possible that you will not be paying any more money to your local electric company for electricity, you may still be charged a monthly connect fee. You will also need to make sure that your homeowners insurance covers the solar system as they will not be responsible for damages such as a tree limb falling on the panels.

Overall, I looked at the program and was quite impressed how consumer friendly it was. I am always looking for the "catch" and I could not really find it. They require a $500 deposit and will only dock you the deposit if you decide to break the contract (as long as you allow them to recover their system and it is in good condition.) They will maintain the system and keep it in good repair throughout the contract like one would expect from a power company. They will even add more panels to your system or subtract panels from your system based on your changing energy needs.

I was pretty impressed, and if they can get enough product together as well as the infrastructure to pull this off, I can see the majority of whole neighborhoods going with this plan. Instant carbon neutrality.

Re:realities? (1)

TapeCutter (624760) | more than 7 years ago | (#17721180)

"REnU program" - That is a fanfuckingtastic idea! When will it get to Australia...oh wait...***rushes of to bank with bussiness plan***

From thier FAQ: "You do not pay the security deposit [$500] until after the solar engineer comes to your house and designs your system. They will show you exactly what the system will look like and only after you sign off on the design do you pay the deposit."

Like any contractor they send a guy around, he gives you the speil and you pay a deposit, so I guess you can judge for yourself the "bogus factor" before opening your wallet. I don't see what you have to lose?

They also state their "factory" will be ready somtime in 2007 and are upfront that the "sign up" phase is a plan to generate institutional investment, a long waiting list of "solid appointments" will attract investors like bears to honey.

If one thing is almost certain, grid power is not going to get cheaper in the next few decades. I think the British slashdotter's can attest to the level of their recent utility price hikes, here in Australia our PM has recently warned of similar future rate hikes of up to 40%.

The only downside I can possibly think of is disposing of old technology, but at least it's in a solid (collectable) form, if this service is succesfull it will be just like someone invented a magic "sequestration" bullet that sucked the C02 from a smokestack and burried somewhere...

...somewhere deep...yes, it's got to be burried deep..oh, and offshore too, don't forget deep and offshore...possibly so far offshore it's in international waters, closer to cuba than florida really....

Re:realities? (1)

sireasoning (576345) | more than 7 years ago | (#17721278)

It is a brilliant idea, and I think it is a disruptive one in that it allows all of those who are aware of the problem to take immediate action. The nice thing about solar is that it is at its most efficient during the most energy intensive times, hot summer days.

Re:realities? (4, Informative)

edwardpickman (965122) | more than 7 years ago | (#17720926)

Do your own research. Some of the information given you is bad. The life expectatncy of photovoltaics is 25 to 30 years, potentially more. The general rule for payback is seven years. If you aren't prepared to pay in advance for that long I guess don't do it but you will get 20 to 25 years of free power so you do the numbers. I'm not sure if California still has the tax credit but they were offering 50% of the cost of the photo volatiacs. Either way it's a good value. The bigger consideration to me is whether to go silcone or flexsible. Silicone cells are more efficent in bright sun but the flexsible cell are more durable and work better in poor light. The downside with silicone cells is if one breaks the panel goes down. The cells are very fragile. Flexsible cells can actually be punctured and still work, I've seen film of them being applied with staple guns. Even so silicone may be the better bet in Southern California due to all the sunshine. In the northern states I'd definately go flexsible Ultimately the descision maker should be how long are you going to keep the house? If you are going to move in five years I'd hesitate. If you plan to be there ten to twenty years go for it. Even if you do sell the house in twenty years the panels will have five to ten years life in them and add considerably to the value of the house. Power costs won't drop in the next twenty years. They have to go up during that time. Fusion ain't gonna happen in the next fifty years. Everyone admits that. Other than large scale coal there's no cheap replacement for current electric sources and even hydroelectric is threatened due water availibility and threats to fish stocks. Nuclear will take many years to get on line and there's still too many problems to make it a major source of power. A government study concluded localized solar was the best solution to Californias energy problems but that doesn't make money for the power companies so little was done to make it happen.

Windmill (2, Interesting)

Flying pig (925874) | more than 7 years ago | (#17720946)

I don't know about your wind levels, but have you considered using a windmill to drive the pool pump? This is far simpler and more efficient than using anything to generate electricity and then using electricity to drive a motor, and inherently more reliable. You do need a positive displacement pump so it will work at any wind speed enough to turn the vanes.

This is far from an impracticable technology. In the days of wooden ships, the Dutch used to buy English ships that had become waterlogged (yes, they do...) fit them with windmill pumps and continue to use them, just letting the wind keep the bilge dry.

To be really clever, if you manage to set up a windmill pumping system, run it in parallel to the electric pump with a simple rotation sensor (two microswitches and a simple cam on the shaft, linked to a timer circuit) so that when the wind stops, the electric pump starts.

Re:realities? (1)

Benaiah (851593) | more than 7 years ago | (#17721494)

Chemicals my dear watson... Chemicals.
Try adding extra Chlorine instead of relying on the chlorinator.
Add extra salt and the right amount of Buffer to protect the chlorine from the sun.
PH balance right.

Then your pumping time will be drastically reduced.

For your pool, sir... (1)

Khyber (864651) | more than 7 years ago | (#17721588)

Make the extra investment and buy several smaller pumps that are more efficient for pumping water form the pool thru filters out to the jets. A pump for each jet would suffice. Switch to (if you're not using one already) a diatomaceous earth filter for your pool to reduce the pressure needed to pass thru something like a sand filter. You can drop that pool pump monthly cost quite easily. :)

Re:realities? (1)

giafly (926567) | more than 7 years ago | (#17721624)

One of the big electricity hogs in our house is the pool pump, and there's not much you can do about that; if you don't pump long enough on the pool every day, it turns green.
Use an opaque cover [google.com], add chlorine [google.com], or just drain the water out. You're right about the solar panels though.

yeah, but (2, Funny)

macadamia_harold (947445) | more than 7 years ago | (#17720712)

Forty states have laws allowing individuals to do this, and many of them offer subsidies and tax breaks for people who do.

Tell that to the boy scout who tried to build a reactor [amazon.com] in his backyard.

Re:yeah, but (1)

bluemonq (812827) | more than 7 years ago | (#17720768)

I really hope you're joking, and that I'm just too tired from working on my homework to realize it. He wasn't trying to build a reactor for electrical power but rather to obtain more useful radioactive material...at least that's the impression I'm under.

Not with your home's current electrical setup. (0, Redundant)

Anonymous Coward | more than 7 years ago | (#17720720)

It takes more than legislation and solar panels to put energy back into the grid. You also need the right gear. It is expensive at the moment, but it wouldn't be if everyone was buying it.

Re:Not with your home's current electrical setup. (2, Interesting)

Gordonjcp (186804) | more than 7 years ago | (#17720906)

You also need the right gear. It is expensive at the moment, but it wouldn't be if everyone was buying it.

It's not a million miles away from the cheap inverters and UPSes you can buy. One important point is this - it must have an incoming mains supply to work. If there is a power cut, it will shut down, and most aren't smart enough to just disconnect from the grid and leave you on standby power. Why? Well, because it needs a phase reference for the incoming mains, and if the power goes down it has no way of knowing what phase it's going to be when it comes back. Imagine if your inverter is pushing out the full -120v when the incoming mains comes back at +120...

It would be possible to build an inverter that would disconnect the incoming mains supply in the event of a power failure, and "slip" the inverter until it's in phase before dropping it back in, but you'd need something like a 100A contactor for that to work.

Re:Not with your home's current electrical setup. (5, Informative)

Ungrounded Lightning (62228) | more than 7 years ago | (#17720996)

Imagine if your inverter is pushing out the full -120v when the incoming mains comes back at +120...

It would be possible to build an inverter that would disconnect the incoming mains supply in the event of a power failure, and "slip" the inverter until it's in phase before dropping it back in, but you'd need something like a 100A contactor for that to work.


Actually, they drop it because grid-tie inverters are REQUIRED to disconnect from the grid when the grid goes down. This is to prevent backfeeding the disconnected island and frying a lineman who's trying to fix the downed wire for your block and thinks the lines are dead when YOU kept them live. (Those pole-pig transformers work just FINE in reverse, so a lineman might grab a line with 12,000 volts on it and a couple kilowatts to keep it that way while he's dancing and trying to breathe.)

Now the EASY way to do this is just to monitor the frequency and voltage, and shut the inverter off when it goes out of spec (meaning the grid is probably dead and the line only looks hot because of the inverter backfeeding it).

For a couple grand more, in the case of some good inverters that are designed for it (such as some of the Xantrex models), you can add a box with a relay, a phase-difference monitor, and a subsidiary "brain" board (or get an inverter with the function built in). (Actually the box in question usually also has the line monitoring circuit and combines with inverters that are otherwise stand-alone non-grid-tie.) That box will disconnect the inverter-and-keepalive-lodds from the line and let it keep going during an outage, then tell it to drift phase until it matches and hook it back up once the grid is back and has stabilized.

Re:Not with your home's current electrical setup. (1)

TooMuchToDo (882796) | more than 7 years ago | (#17721200)

Didn't Xantrax used to be Trace Engineering? Them were fine inverters. Not only would they disconnect from the grid when they detected islanding, you could remotely monitoring the over serial (hopefully via IP one day) and they could be stacked to output 240VAC.

Re:Not with your home's current electrical setup. (1)

Technician (215283) | more than 7 years ago | (#17721320)

For a couple grand more, in the case of some good inverters that are designed for it (such as some of the Xantrex models), you can add a box with a relay, a phase-difference monitor, and a subsidiary "brain" board (or get an inverter with the function built in). (Actually the box in question usually also has the line monitoring circuit and combines with inverters that are otherwise stand-alone non-grid-tie.) That box will disconnect the inverter-and-keepalive-lodds from the line and let it keep going during an outage, then tell it to drift phase until it matches and hook it back up once the grid is back and has stabilized.
--


Outback systems has this down to an artform in a very robust package.
http://www.wholesalesolar.com/products.folder/inve rter-folder/outbackGVFX3648.html [wholesalesolar.com]
This one has the advantage of both a battery system which operates at night in an outage, and power company gridtie.

Most gridtie systems do not use batteries. they use the power company as a battery. Batteryless systems are prone to power outages.

Re:Not with your home's current electrical setup. (1)

Gat0r30y (957941) | more than 7 years ago | (#17721036)

It would be possible to build an inverter that would disconnect the incoming mains supply in the event of a power failure, and "slip" the inverter until it's in phase before dropping it back in, but you'd need something like a 100A contactor for that to work. you don't need a 100A contactor for it. You use DC straight from your backup until power is restored. No need to make things complicated.

Non conventional (3, Informative)

TheCybernator (996224) | more than 7 years ago | (#17720734)

When talking abt non-conventional sources of energy, solar power technology is yet become economic. I would rather install a wind mill on my roof instead a solar plates.

while back here in third world countries we use other non-conventional ways to save on energy bills like
Bribe the Electricity Engineer or
Tap electricity directly from pole without any meter

Re:Non conventional (3, Funny)

scoot80 (1017822) | more than 7 years ago | (#17720764)

You live in Holland?

Re:Non conventional (3, Funny)

TheCybernator (996224) | more than 7 years ago | (#17720818)

No. India. And why i would prefer wind mill over solar panels is because there is higher probability to find the wind mill still on my roof after vacation than solar panels :)

Re:Non conventional (1)

Gordonjcp (186804) | more than 7 years ago | (#17720944)

In the UK, you can buy a complete windmill set that will feed back to mains for around £1500. It puts out a couple of kilowatts, and is available in large DIY shops.

Where the icy cold beer is on the house (4, Informative)

BillGatesLoveChild (1046184) | more than 7 years ago | (#17720752)

This is more widespread than you realize. Aussies have been doing it for a couple of years now. Just the thing for a desert country where it seldom rains:

http://www.smh.com.au/news/National/Where-the-icy- cold-beer-is-on-the-house/2004/12/06/1102182229401 .html [smh.com.au]

Re:Where the icy cold beer is on the house (1, Funny)

Anonymous Coward | more than 7 years ago | (#17721034)

Never trust a man who's last name is Shakeshaft.

Re:Where the icy cold beer is on the house (1)

cute-boy (62961) | more than 7 years ago | (#17721240)

G'day

Sorry there is nothing widespread about use of solar energy in Australia. Nor is it likely there will be much incentive (beyond tokenism) for the home owner to invest.

Here is Australia we have coal, and lots of it. We want to sell it. We have lots of uranium ore. We want to sell that too. Our government is reciting a mantra that these energy sources are clean, when handled properly, and there are never any problems. Our governments are prepared to rip up world heritage areas to get at these commodities. They are prepared to destroy other parts our lands to bury them.

Without our commodities the economic boom time Australia is in will cease to exist.

I'd love to use some of the sunlight that falls on my roof, and turn it into electicity, if but I could afford to do so.

I live in hope that solar tech will come down in price just like computers did...

-R

Re:Where the icy cold beer is on the house (1)

BillGatesLoveChild (1046184) | more than 7 years ago | (#17721302)

By widespread I meant that someone outside the US had done it first :-)

Yes, that solar program is limited to Sydney and as the linked SMH.com.au article says the people in the program do it for the love rather than the money. I'm not aware of any other states that are doing it. The Aussie Government does give a $4K rebate for Solar Home Owners, but its chickenfeed compared to what they're investing the nuclear and coal industry.

It really does work. (5, Informative)

Calibax (151875) | more than 7 years ago | (#17720754)

Back in 2003 I decided the time was right to go green. At the time I was paying about $2900 a year for 15,500 KwH, and I figured I could make the money back in a reasonable number of years. After many discussions with local solar installers I picked one and in December 2003 I had 48 panels, each 60 inches by 30 inches, installed on my roof and three inverters on the side of the house to convert the DC output to standard household AC.

The panels generate approximately 7.5kW AC (8.8kW DC). The total cost was $65,000 but with a grant from the State of California and State tax credits, the total cost was reduced to just over $31,000. Since then I have been paying only the minimum price for electricity service (around $5 a month) to cover the cost of the meter rental. As electricity rates have increased a bit (and no doubt will continue to increase) I calculate that I will recover my costs approximately 8 years after installation, and I will then start to save money. The life of the panels should be around 30 to 40 years

It's worth remembering that you need to make certain your roof is good for the years the panels will be operating, so for some it will also mean installing a new roof first. That wasn't an issue for me as I have an ornamental metal tile roof that should last much longer than the panels.

Essentially, I use the power utility as my batteries - during sunny days I generate much more electricity than I use and the excess goes into the grid, and then I use power from the grid on rainy winter days and during nighttime. I get credited for electricity sent to the grid, and yes, the meter really does run backwards.

One neat trick is that I don't have to generate the equivalent of all the energy I use to break even. I'm on a utility company plan where the electricity I use during peak summer times (noon to 6pm) is very expensive - around three times normal rates - but off-peak usage is about 70% of normal rates. But I get credited at the rate in place at the time of day the electricity is generated. Because my installation generates the majority of the electricity during the peak times, I get credited for those KwH at the high rate and when I need to use electricity at night I pay the reduced rate. As an example of how effective this is, last year I generated 12,400 KwH and I also used 3,600 KwH from the utility company. But at the end of the year I had a credit balance of $380.

There's one gotcha there - if you have a debit balance at the end of the year, you have to pay it. But if you have a credit balance, that gets lost. Ideally you want to generate just enough electricity so that your adjusted balance is zero, but that's pretty hard to judge. In any case, you want ample extra capacity just after installation as the panels reduce their efficiency by about 0.5% to 1.0% per year.

Re:It really does work. (1)

nametaken (610866) | more than 7 years ago | (#17720980)

That's really good info, but it's obvious that you're reasonably wealthy. You have room for 48 panels, can manage a 31k installation, handled swinging the 30k difference in tax credits, and have a decorative metal roof. This is not something your average Chicago suburbanite is going to be able to swing effectively.

Is there another method that's more reasonable for joe sixpack?

Re:It really does work. (1)

blankoboy (719577) | more than 7 years ago | (#17721026)

Great stuff! You mention that the life of the panels is 30-40 years. How do they stand up to hail storms, errant baseballs landing on your roof, etc and what is the cost to replace a single panel? Also, what is the expected MTBF of the inverter+batteries and cost to replace them?

I would love to have a setup like that and then have a fully electrical car...no diesel/hybrid but fully electric.

Re:It really does work. (0)

Anonymous Coward | more than 7 years ago | (#17721080)

Works well in your current scenario. I've done the math before, and it wasn't worth it for me.

It was worth it likely because if your grant (not available here), likely higher electricity rates (along with pay 'em at 70% and get credited at 300%).

At our current rates (and personal usage), it would take me more like 15 years to pay back 31000$ @ 7% interest. Without that grant, we're taking about at least 30 years -- not counting the cost of replacement batteries, maintenance or anything like that (and by what you say, my panels could be 30% weaker by then, which I hadn't accounted for either). And that'll be close to the end of life of those panels. And that's assuming California's sun exposure, which is FAR better than what we get here (always cloudy, in Canada).

That's a lot of money to pay up front, that would end up never paying for itself (here at least), an additional debt well in the 5 figures, and it would not follow if I ever move (just might lose money on the setup if I end up selling the house too).

No thanks. At least not yet. Maybe in the future, once the price is down, efficiency is up, and electricity costs have gone up - maybe then it'll be worth it. Until then I do my best to reduce power usage (CFLs, power management, not cranking heat or AC to the max, etc)

Re:It really does work. (5, Interesting)

dada21 (163177) | more than 7 years ago | (#17721322)

And here is the reason you pay so much in taxes, folks. Those grants come from somewhere. Whether or not you like green power, if you live near this guy or in this guy's state (or worse, if it was a federal grant), you're paying for it. Out of your pocket. Today. If it was a federal grant, that money is debt money -- it could take a generation to pay off his grant, federally.

Government has no right to steal from me, or you, to pay for this guy's pipe dream. If he really wanted to do it, he should have done it with his own dollars, not robbing the tax payer of anything.

Of course the average greenie socialist here would mod me down, but I speak the truth -- there is no such thing as a free lunch, and this guy will get one after only 8 years or so. On your back.

Re:It really does work. (4, Insightful)

retrosteve (77918) | more than 7 years ago | (#17721460)

Well, I'll be the greenie socialist then.

The reason taxes work when they do is that some things fall under the "common good". If we just asked everyone to pay only for services that benefit them personally, we'd have only private schools, few medicines, and likely no roads or traffic lights.

Some things just only work if everyone is forced to pay a bit for them. But look at the benefits in this case. If the government takes some of your tax money to pay all the people who want to make their own power, everyone benefits through lower load on power stations, decreased demand for power (which lowers prices!), decreased pollution and demand for foreign oil.

Obvious win-win.

Re:It really does work. (1)

djmurdoch (306849) | more than 7 years ago | (#17721472)

The environmentalist response to your complaint is that anyone burning fossil fuels is stealing from future generations: making their climate worse, depleting non-renewable resources. If the production of the solar panels isn't just as bad, then it's a reasonable thing for government to be funding.

That's what government is supposed to do: fund things with long range general benefits, because if the costs go to the individual but the benefits are general, the individual won't pay, and the benefits won't come.

Re:It really does work. (1)

Technician (215283) | more than 7 years ago | (#17721398)

Essentially, I use the power utility as my batteries - during sunny days I generate much more electricity than I use and the excess goes into the grid, and then I use power from the grid on rainy winter days and during nighttime.

Have you considered replacing one of your inverters with one from Outback Systems to fee your critical load (bath, hall, bedroom lights, freezer, fridge, computer, & TV?

They have a very nice grid tie system using batteries which is power outage proof.
http://www.wholesalesolar.com/products.folder/inve rter-folder/outbackGVFX3648.html [wholesalesolar.com]

Greenhouses too (3, Funny)

cerberusss (660701) | more than 7 years ago | (#17720774)

In the Netherlands, farmers who plant crops in greenhouses always have petroleum gases driven generators to warm the greenhouse in the winter. In summer, these generators feed back into the grid.

Re:Greenhouses too (1)

pipatron (966506) | more than 7 years ago | (#17720858)

That sounds expensive, ineffective and unfriendly for the environment. If they are connected to the grid anyway, why not use the electricity directly instead of burning up fossil fuel in ineffective small-scale generators?

Re:Greenhouses too (1, Informative)

Anonymous Coward | more than 7 years ago | (#17720960)

It's because we have a large natural supply of gas. Large bubble near Slochteren.
And yes it is insane to power greenhouses with gas, just to grow crops that grow natural 2000km down south; Did I mention greenhouse veggies taste like water?
And yes it's insane that the government tosses billions of subsidies to maintain this.

Whats even more insane is that last year, the government decided to release the energy supply to a free market. Because of this, the price of gas went up, since energy suppliers can only sell a certain amount of gas, on a first come, first serve basis. So greenhouse farmers pay more for gas, the government pays more subsidies, the customer pays higher gas prices, and the farmers products' prices go up as well. At the same time poor farmers in Marocco and Spain, with superb quality vegetables, can't get a foot on the ground.
Gotta love capitalism.

The gp wasn't being funny, it's the truth.

Re:Greenhouses too (3, Informative)

Calinous (985536) | more than 7 years ago | (#17721076)

Because the total heat contained in the natural gas is used - some is generated as electricity, and the rest remains as residual heat in the greenhouses. 100% efficiency during winter

Re:Greenhouses too (2, Informative)

cerberusss (660701) | more than 7 years ago | (#17721102)

Actually, this is very environmentally friendly. Burning liquid petroleum gas is very clean, and cheap for the farmer. The grid would be severely loaded if directly tapped into for the scale that the huge greenhouses have.

Also, the generators are thoroughly insulated and because of this particular application (greenhouse), the excess warmth is directly used. This results in an extremely high energy/warmth ratio.

wait a minute.... (0)

Anonymous Coward | more than 7 years ago | (#17720776)

If i recall doesn't take more energy to make a solar pannel then the energy it will produce in its life time? I mean sure they are good for remote locations where getting power lines would cost large sums of money but, for a place where power is readily aviable it is a waste not to mention the energy/money wasted to create the thing.


So don't go out and waste your money for a small tax break because you made your own power. For as far as i can tell you will just pay more money in the long run espically when those cells die.

Re:wait a minute.... (1)

Ungrounded Lightning (62228) | more than 7 years ago | (#17721132)

Big fat myth. They make far more power than it takes to make them.

But even if they didn't, you're not using the right comparison.

First: There are two basic kinds of power: Low-quality heat and high-quality stuff like shaft horsepower or electricity. To go from the low- to the high-quality form you have to pay the "carnot-cycle tax". Most of the energy used to make panels is in the form of heat - to smelt metal, refine silicon, and the like.

If you want heat from the sun for an industrial process you DON'T use photovoltaic to get high-quality electricity and then turn it into low-quality heat energy in a resistor. You can get a LOT more at a FAR lower cost and higher efficiency by collecting it directly.

Grids start out with fuel, burn it to generate low-quality heat, then run that through a heat engine to generate high quality energy, first as horsepower and then as electricity. Generation plants and power grids are FAR from a hundred percent efficient (and much of the inefficiency is that heat engine), so they consume far more energy than they deliver. Yet you don't hear the greenies claiming that makes them a net loss, eh?

Second: Panels deliver their output as high-quality electricity at the load site. You may have to store it to cover cloudy and dark times, but that's about it. Grids generate it somewhere else, then transport it. So grids have transmission losses. More inefficiency, more fuel burned to make the delivered high-quality electricity.

But (as with panels) you also have the energy cost of construction of the grid - or at least your pro-rated share of it: Smelting metal for transmission lines, generators, boilers, turbines, transformers, guy wires, towers, fittings, electric meters, breakers, and surge arresters. Melting sand for glass insulators. Cutting trees and treating them to make poles. Fueling the machinery to cut the right-of-way for the lines, haul the parts to the site and drive the workers back-and-forth, and erect and test the lines. (Not to mention consumption of the land under the right-of-way, which is largely taken out of service for other purposes, whether residential, agricultural, industrial, recreational, or ecological.

The cost of the instalation is a pretty good measure of the combined costs - energy, labor, and resource-consumption - of building the infrastructure, generating, and delivering the high-quality electric power to the load. Energy costs are the bulk of it in both cases. You find that, even with current technology, photovoltaic power beats grid power in a number of applications. Generally that's new construction in remote areas (where you can avoid the cost of building the last mile(s) of the grid feed and use that to pay for the instalation), small loads (road signs, yard lights, emergency phones, etc.) where it's cheaper to slap a panel on 'em than run a line, and maybe sites where you need backup power - and can convert it to full renewable energy by adding generation and tweaking the choice of battery size and inverter design. With technology improvements and rising fuel costs the breakeven point is reached in more areas. With enough improvement the grid may become obsolete in most places where reliable sun and/or wind is available.

Augh. Doesn't. Make. Sense. (1)

Ihlosi (895663) | more than 7 years ago | (#17720792)

Their electricity meter runs backward. Solar panels on their barn roof can often provide enough for all their electricity needs. Sometimes -- and this is the best part -- their solar setup actually pushes power back into the system.



Augh. This doesn't make sense. No, not the whole solar setup, but the phrases above. If the meter is running backward, then the system is feeding excess power to the grid. If the meter is running backward while the system isn't feeding power to the grid, it's broken or manipulated.



Anyway. This stuff has been around for years in other parts of the world (complete with, omigosh, government subsidies for the generated power - you're getting 3x the price for power you sell than for what you take out of the grid). It's news in the US ? Yawn. Wake up and smell the coffee.

Re:Augh. Doesn't. Make. Sense. (0)

Anonymous Coward | more than 7 years ago | (#17720902)

That's exactly what it's doing.

From TFA:
"Sometimes - and this is the best part - their solar setup actually pushes power back into the system."

You can do this without solar panels. (5, Funny)

Peter Cooper (660482) | more than 7 years ago | (#17720800)

Back in the 'good old days' you could hack the meter and switch the wires around so that the meter would run backwards, even though you'd still be getting electricity. A one-time friend of the family did this in a shop he owned. He figured he'd switch it, operate for a week on, week off, so the bill would be low, but not too low. Unfortunately he forgot about this arrangement and the meter showed him to be $1000+ in 'credit' with the electricity board saying they were going to be visiting in a week or so. Panic ensued, and he bought a bunch of electric kettles and rigged them up 24/7 to suck juice from the grid to get back into the red.

Re:You can do this without solar panels. (1)

Technician (215283) | more than 7 years ago | (#17721422)

A one-time friend of the family did this in a shop he owned. He figured he'd switch it, operate for a week on, week off, so the bill would be low, but not too low.

Rewireing a meterbase often with aluminum wires is a great way to form high resistance points in the wire. Can you say house fire?

Solar Living Center will teach you how (2, Informative)

Anonymous Coward | more than 7 years ago | (#17720814)

The people behind the current Solar Living Institute (www.solarliving.org) have been doing stuff like this for probably over 30 years, back when it was called "Real Goods", which sold solar electric panels and prided itself on "taking people off the grid".

They sell a book Solar Living Source Book [solarliving.org] (now in its 12th edition) which tells you how to take your home off the grid using solar panels, plus they offer courses http://www.solarliving.org/workshops/ [solarliving.org]. They also run the Solar Living Center [solarliving.org], which is a self-sustainable solar energy building/store/headquarters in Hopland, California.

net metering to start your own backyard e-trading (4, Interesting)

viking80 (697716) | more than 7 years ago | (#17720860)

The consumer is offered two choices from the utility:
A. peak rate at $0.40/kWh and off-peak at $0.20kWh
or
B. fixed rate at $0.35/kWh

Now two neighbours sign up for the two different rates, and start their own little energy trading:

Off peak, Neighbour A buys at $0.20 from utility and sells to neigbour B for $0.35. B resells to utility.

During peak hours, Neighbour A buys from B at $0.35m and sells to utility for $0.40.

With a 400A service, they can 800,000kWh a year and make a profit of $80k!

Have fun

Re:net metering to start your own backyard e-tradi (1)

mcrbids (148650) | more than 7 years ago | (#17721062)

Sounds great, except that both neighbors are plugged into the same grid. Run the wires == no movement. Nothing happens. Nada. You need to have a difference in electrical potential. Sounds great, but it just wouldn't work...

Re:net metering to start your own backyard e-tradi (0)

Anonymous Coward | more than 7 years ago | (#17721202)

Yes, and the package on you floor does not automatically ship itself either. this is done easily.

Oregon does not have to run their entire state grid on 112V to sell electricity to California at 110V. (I know it is not 110V, but just to illustrate)

Re:net metering to start your own backyard e-tradi (1)

ZombieEngineer (738752) | more than 7 years ago | (#17721120)

A 400 Amp service would be getting into the "small to medium business" catagory.

At which point your meter would be read monthly and you only have one choice of rate (peak/off peak).

I would give your suggestion only 28 days before the power company moves in and changes your plan.

ZombieEngineer

Re:net metering to start your own backyard e-tradi (1)

The Master Control P (655590) | more than 7 years ago | (#17721176)

The energy utility would see though this scam immediately for several reasons:

- The neighbors claim to be pushing 96KW of power onto the network, while in reality they're just shunting it from A's tap then back through B's tap, resulting in a net draw due to resistive and transformer losses. 96 missing KW won't go unnoticed.
- Nothing you can legally put on residential property will generate 96KW of electric for any length of time. This will generate suspicion.
- Funny, A's meter runs back while B's runs forward and vice-versa. Bill, take a truck and check this out...
- I'm fairly certain that the utility and/or city have to send out an inspector before you can connect a grid intertie. Said inspector will note the lack of any generating equipment.

ps: Be thankful that residential pole transformers are current-limited when you try and connect the wires.

Re:net metering to start your own backyard e-tradi (1)

Ihlosi (895663) | more than 7 years ago | (#17721254)

- Nothing you can legally put on residential property will generate 96KW of electric for any length of time.

So you're not allowed to park a car on a residential property ?



A car engine, if connected to a generator, could do it.

Re:net metering to start your own backyard e-tradi (1, Insightful)

Anonymous Coward | more than 7 years ago | (#17721376)

Off peak, Neighbour A buys at $0.20 from utility and sells to neigbour B for $0.35. B resells to utility.

You're going to need some equipment to do this, just running wires between both meters won't do. This would require significant investment, and things that wouldn't necessarily go unnoticed (an electrician installing 400 amp lines between 2 neighbours might ask some questions). And there will be losses.

During peak hours, Neighbour A buys from B at $0.35m and sells to utility for $0.40.

With 10% losses, you're basically breaking even here.

With a 400A service, they can 800,000kWh a year and make a profit of $80k!

If they had 200A service before, and moved to 400A (200A extra for this), they'd be getting closer to 400,000kWh (half of whatever you counted), and if you add some losses and such, and you'd only be doing profit off-peak hours (not 24/7), so less than half the profit you mentioned too -- minus the price of getting 400A service installed on both houses and all the equipment required.

And it's likely illegal to sell them back their own electricity indirectly (TOS?), and I wouldn't want to get caught doing it.

And that only works if they pay you for the electricity "generated" -- often they'll deduct from your bill, but won't pay for any extra, in which case one would have a 0$ bill, and the other would have a insanely high bill (more than both of you used to pay combined).

Not a good idea.

Making money from electric co (3, Interesting)

hyrdra (260687) | more than 7 years ago | (#17720912)

What is to prevent people from storing electricity (in batteries) during off peak hours and then selling it back during peak hours and generating a profit?

Re:Making money from electric co (1)

M. Baranczak (726671) | more than 7 years ago | (#17721010)

Batteries are inefficient. The energy wasted on battery leakage would probably cancel out any profits. Or maybe not... anybody here qualified to work out the math on this?

And even if people do it - so what? It just means that they increase the peak capacity of the grid as a whole. The power companies would want to encourage that sort of thing.

Re:Making money from electric co (3, Insightful)

Ihlosi (895663) | more than 7 years ago | (#17721016)

What is to prevent people from storing electricity (in batteries) during off peak hours and then selling it back during peak hours and generating a profit?



The forces of nature. That is, physics and economics. Physics because it limits the efficiency of storing energy in batteries to impractical amounts, economics because batteries that size are frickin' expensive.

Alternative Storage Methods? (1)

cyclomedia (882859) | more than 7 years ago | (#17721378)

Slightly off topic but something i've been wandering about, if you're time-shifting your generated electricity by only a few hours - using solar at night is a good example - are there better or just more interesting ways to store the *energy* than good old lead-acid and the like?

One idea i had was to spin up a largish gyroscope, (though you might need to give it a kick start...attach a bicycle!) whilst "charging" then change a gearbox to drive an alternator when "discharging". The efficiency of this could probably be quite good over a few hours, provided you keep it's bearings well greased.

Another was clockwork: wind a spring when charging and again, run the power through a gearbox to an alternator when discharging, you could even use a clutch to directly wind the spring via wind or water power (though i suspect the former wouldnt have the torque) that way you wouldnt lose energy converting it to/from electricity in the first instance. AFAIK though it's hard to regulate clockwork to provide a continuous reliable RPM, which is why clocks tick instead of running smoothly.

Or good old gravity power: Charge by pumping water uphill, Discharge by releasing it downhill, this probably wouldnt be that great on a less than reservior scale, you'd have to reinforce your attic and make it into a huge tank, and do the same for the basement. on the other hand the same water might be able to be used as a heat store/heat sink for temperature regulation.

Havent researched any of this but i suspect that using huge tanks of hazadours chemicals to electolytically store electricity isnt exactly environmentally sound when you think about production and disposal.

Only efficient at industrial scales (1)

Ihlosi (895663) | more than 7 years ago | (#17721442)

Or good old gravity power: Charge by pumping water uphill, Discharge by releasing it downhill, this probably wouldnt be that great on a less than reservior scale, you'd have to reinforce your attic and make it into a huge tank, and do the same for the basement. on the other hand the same water might be able to be used as a heat store/heat sink for temperature regulation.



This method is actually used, and yes, it only makes sense if you're in the mountains and can pump water between two lakes/reservoirs.


Something similar, just with air pressure, is also in use. However, they are not using air tanks, but old mineshafts instead, since afaik the efficiency of an air pump goes down as the pressure difference increases, so you need a huge volume to store energy in a small pressure difference.

Re:Making money from electric co (1)

delvsional (745684) | more than 7 years ago | (#17721404)

Actually power companies do this with two lakes. one being at a higher elevation. during off-peak hours they pump water into the upper lake(storing the energy) and during peak hours they let it flow back down. they use the same pumps to generate the electricity. it is only about 35 percent efficient but that is still enough to overcome the price difference. the price difference is much greater that 20 and 40 cents.

Catch Up (2, Interesting)

CmdrGravy (645153) | more than 7 years ago | (#17720958)

I'm surprised the US hasn't been doing this before, I think we've been able to do this for years in the UK and it's a pretty obvious development really.

I'm not sure how well Solar Power works here though ;-)

Re:Catch Up (0)

Anonymous Coward | more than 7 years ago | (#17721366)

Does the article say that this is something completely new in the US? It isn't.

Re:Catch Up (1)

Oswald (235719) | more than 7 years ago | (#17721452)

The AC is correct (if a bit rude). Any idea that has 40 state laws supporting it has at some point enjoyed not only widespread grassroots support, but a period of political currency. This meter-reversing stuff goes back to the '80s in the US.

Hydro is good for this. (5, Interesting)

rhesuspieces00 (804354) | more than 7 years ago | (#17720966)

My dad had a friend a while back that did this, I think maybe in Oregon or Washington, but I don't recall. He had a large property with a decent sized stream running through it, and set up a water wheel. It generated A LOT more power than he used, so he was constantly pumping power back into the grid, which his electric company paid him for, at something like one fifth of what he would pay for the electricity if he was drawing it. The startup cost wasn't that high, as he was an electrician and set it most of it up himself, and was way more cost effective than solar panels at the time (I don't know if that is still true, this was 10 or 15 years ago). He wasn't just saving money, but actually turning a profit of a couple thousand dollars a year.

I think some time later the regulations might have changed and the power company would no longer pay him, but at least he still had electricity that was essentially free.

An easier method: (1)

loic_2003 (707722) | more than 7 years ago | (#17721152)

All you have to do is swap over the input and output cables on the meter and it'll run backwards. Eventually, the electricity company will give you money to use their service!
duh.

Slightly off topic, but ... (1)

OneSmartFellow (716217) | more than 7 years ago | (#17721220)

... Is it worth lobbying for a industrial AC/DC rectifier in each house at the meter.

I shudder to think what percentage of the total cost of each electric/electronic device is made up of the 12 vdc power supply.

Said Supply usually lasts less than three years, replacements are generally quite expensive.

Disposal of the original is bad for the environment.

And is is obviously less efficient to condition power for each device than to condition it in one centralized place.

It seems that the debate over AC vs DC should be renewed, but I don't need to see an elephant being electrocuted as a part of it.

Re:Slightly off topic, but ... (3, Interesting)

Technician (215283) | more than 7 years ago | (#17721536)

Is it worth lobbying for a industrial AC/DC rectifier in each house at the meter.


No. Do the math. From the post it looks like you are advocating a 12 volt system for the house. Right now a 20 amp breaker feeds a 12 AWG wire just fine and you can plug in a 1500 watt hair dryer in the bathroom which is maybe 40 feet from the meter. At full load, the voltage at the outlet may drop a couple volts so you are talking 12 amps current at 2 volts in the wire or 24 watts lost in the entire length of wire.

Now the 12 volt version. From 120 volt to 12 volt at the same wattage (Volts * Amps for a resistive load) you will now need to draw 120 amps instead of 12 for the blow dryer for the same 1500 watts. If you were dumb enough to try using the same 12 AWG wire the 2 volt drop is now 20 volts. OOPS.. We seem to be short 8 volts in the negative direction to get 120 Amps to the bathroom outlet at zero volts. Lets see if it were possible the 20 volt drop in the wire at 120 amps would be 2400 watts of heat in the 40 feet of wire. Can you say HOT!. Maybe we need a larger wire size. Maybe a size big enough to handle the original voltage drop of a couple volts. Our original setup at 120 volts has less than 2% voltage drop. At 12 Volts we now have a little under 20% voltage drop. Hmm we need to go to even bigger wire to reduce the voltage drop to less than .2 volts in 40 feet.

You do the math. Find a copper wire table and find out what AWG wire is required to handle 120 Amps with only .2 volts drop. Don't forget the current in a 40 foot length travels both ways on 2 conductors, so figure it for 80 feet.

When you are done with the math you will understand why we use 120 volts and some countries use 240 volts. You may get electricuted in an accident, but you don't need welding cable for your hair dryer.

My 1KW inverter in my car uses Welding cable for leads and the length is kept to under 3 feet total to keep the voltage drop within limits.

Easier ways to make it run backwards... (1)

mrcpu (132057) | more than 7 years ago | (#17721242)



I'm thinking that just running an extension cord over to my neighbors and wiring it up to my meter will help, w/o all that nasty solar garbage on my roof, and w/o all the expense...

Or go to home depot, get a nice 6000 watt generator, plug it in and let it run the meter backwards...

Getting the meter to run backwards isn't that complicated... The fact that people find this news is amazing...

Subsidies (1)

gggggggg (862650) | more than 7 years ago | (#17721296)

In some countries which are actually interested in the Kyoto Protocol there are strong subsidies for solar power generation. The electicity companies are required by law to buy off from you the electricity you generate (from solar power) at over 500% of the current selling price at which you can buy from them.
In fact, due to this, it is never a good idea to power your home from your own generated electricity. It is always more efficient (economically) to buy your electricity at rate 1x, and sell the one you generate at rate 5x.

bad bad bad (1, Interesting)

micktaggart (1047954) | more than 7 years ago | (#17721332)

Connecting these devices can create all kind of havoc in a high voltage electrical grid. It wouldn't surprise me if one of these solar panels or windmills will cause an enormous blackout in the near future.
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